Leps spinning on pin

[alice]

Hi all, 

I am working on IDing lep specimens that were pinned a few weeks ago by a colleague. Most of the specimens are spinning on their pins. Why does this happen, and how can I prevent this from happening? 

I rarely have specimens spin when I pin. 

Thanks!

[Adam Cotton]

Probably these specimens have been stored in papers, relaxed (rehydrated) and spread rather than being spread freshly collected. Specimens spread fresh from collecting very rarely ever spin on the pin as the contents of the body glue the pin in place as it dries.

The longer the specimen has been stored dry the greater chance that it may spin on its pin, but other important factors include whether the specimens were internally decomposed before originally drying after capture and whether they had been eaten internally by museum pests before relaxing them. Another reason could be that the owner (in this case your colleague) could have caused them to become loose on their pins due to the way they were handled after removal from spreading boards.

It may help if you mention which group of Leps the problematic ones belong to, a wide range of different families and sizes, or all relatively closely related.

Adam.

[bobw]

I've also found that specimens are much more likely to spin on black enamelled pins than stainless steel.

[larrycurlymoe]

When that happens, I usually put a small drop of glue on the pin to stop the spinning. Before doing that, you should check with your colleague. Some institutions may frown on it, but it works.

[Adam Cotton]

If I have a "spinner" I slide the specimen up the pin towards the head and then put a small drop of glue on the pin at the right height and slide the specimen back down the pin onto the glue.

Adam.

[wollastoni]

Feb 4, 2021 18:29:19 GMT bobw said:

I've also found that specimens are much more likely to spin on black enamelled pins than stainless steel.

True !
Another good reason to use only stainless steel pins ! 

The main reason being : black enamelled pins will one day rust ! It could be after 20, 50 or 100 years depending of your country climate... and it is a disaster for old collections (which are scientifically the most interesting).
So guys, please spend 50 cents more and purchase stainless steel pins only !   

[Paul K]

Two years ago I replaced all my pins to stainless ( about 1000 specimens). I relaxed, change pin and remount to dry all of them.
Huge task already and I can’t imagine to do that for few thousands.
So sooner to start using stainless pins the better.